Fastener feeding apparatus drive control means

ABSTRACT

A drive control means by which headed parts such as screws or other fasteners contained in any order in a bulk supply means such as a hopper are supplied continuously in a required alignment to a distributor, and supplied individually from the distributor to a power operated fastening tool. The drive control means has sensing elements which detect when the fastening tool requires a fastener to be supplied thereto, and actuates the distributor to supply a fastener accordingly, and which detect the state of supply of fasteners to the distributor, and actuate a means to supply fasteners from the bulk supply means only when necessary, whereby a constant reserve is maintained in readiness for immediate supply to the distributor and to the fastening tool. The entire drive control means is operated from a single source of pneumatic power, and may be used directly in association with feeding apparatus for fasteners of different sizes.

United States Patent 11 1 Mizu et al.

[ Apr. 8, 1975 1 1 FASTENER FEEDING APPARATUS DRIVE CONTROL MEANS [73]Assignee: Matsushita Electric Industrial Co.,

Ltd., Osaka, Japan 221 Filed: Nov. 20, 1973 21 Appl. No.: 417,529

[30] Foreign Application Priority Data [58] Field of Search 221/9, 10;144/32; 29/211, 29/240; 227/114, 116

[56] References Cited UNITED STATES PATENTS 3,265,273 8/1966 .lanus227/116 X 3,305,155 '2/1967 Willis 1 1 227/116 3,583,451 6/1971 Dixon144/32 3,642,039 2/1972 McGee 144/32 3.779.422 12/1973 Mori ct al.221/10 Primary E.\'aminerAndrew R. .luhasz Assistant ExaminerW. D. BrayAttorney, Agent, or FirmWender0th, Lind and Ponack 57 ABSTRACT A drivecontrol means by which headed parts such as screws or other fastenerscontained in any order in a bulk supply means such as a hopper aresupplied continuously in a required alignment to a distributor, andsupplied individually from the distributor to a power operated fasteningtool. The drive control means has sensing elements which detect when thefastening tool requires a fastener to be supplied thereto, and actuatesthe distributor to supply a fastener accordingly, and which detect thestate of supply of fasteners to the distributor, and actuate a means tosupply fasteners from the bulk supply means only when necessary, wherebya constant reserve is maintained in readiness for immediate supply tothe distributor and to the fastening tool. The entire drive controlmeans is operated from a single source of pneumatic power, and may beused directly in association with feeding apparatus for fasteners ofdifferent sizes.

6 Claims, 23 Drawing Figures PATENTEDAPR 8 I915 SHEET [11 OF HPATENIEDAPR 8l97 5 SHEET 0 [1F 11 FIG. 7

PATENTEDAPR 8 I975 SHEET B50? 11 FIG. 8

PATENTE 8W5 3.875.982

- sum new 11 53 7 pwwa gzb PATENTEDAPR 8191s 3.875.982 SHEET 07m 11 FIG.

PATENTEUAPR' ems SHEET 08 0F 11 FIG. /4

PATENTEDAPR ems SHEET [38 8F 11 FIG. 16

PATENTED 9 5 SHEET mm H 3.875.982

FIG. /8

FASTENER FEEDING APPARATUS DRIVE CONTROL MEANS The present inventionrelates to a drive control means, and more particularly to a pneumaticdrive control means for automatically effecting a continuous supply ofindividual fasteners, such as screws, or rivets, to a required fasteningdevice.

Fastening operations by means of screws, rivets, or similar elements arecarried out on a large scale in many branches of industry. To facilitateand speed up such fastening operations it has been known to employ ameans for automatic feed of individual fasteners to a power operatedscrewdriver, or similar fastening device. Such automatic feed means mustto be controlled by a drive control means which is accurate andreliable, and which ensures that fasteners are delivered to a fasteningdevice in accordance with the needs of the fastening device, is, that assoon as the fastening device has attached one fastener to a requiredobject, another fastener is rapidly supplied thereto, in readiness forthe next fastening operation. Conventional drive control means makecombined use of electrical power and pneumatic power in order to effectcontrol of automatic fastener feed. This combined use of two differentsources of power has the evident disadvantages that the drive controlmeans as a whole is made more complex, and as well as being initiallyexpensive, is also less reliable, since there are two possible sourcesof failure.

It is accordingly an object of the invention to provide a drive controlmeans which employs only a pneumatic power source, and wherebyfasteners, such as screws, or rivets, are supplied continuously from abulk supply means to a distributor, and fed individually from thedistributor to a fastening device, in accordance with the needs of thefastening device.

It is another object of the invention to provide a drive control meanswhereby a removal means such as a rotarydrum, is actuated to removefasteners from a bulk supply means, such as a hopper, only when suchremoval is necessary to maintain a constant supply of fasteners to afastening device, thereby raising efficiency and reducing running costsof an automatic feed means.

It is a further object of the invention to provide a drive control meanscomprising one or more low airpressure detection means for the detectionof the state of supply of fasteners or other objects on a feed line.

It is a still further object of the invention to provide a drive controlmeans which is adaptable directly, and unchanged, to control ofautomatic feed systems for objects of different sizes, thereby renderingunnecessary the purchase of different automatic feed means for feed ofobjects of different sizes.

In accomplishing these and other objects, there is provided, accordingto the present invention, a drive control means comprising first andsecond pneumatic circuits, air being supplied to both circuits from asingle source, the first circuit being for the control of a rotary drumwhich removes fasteners from a bulk-storage hopper and onto a feed chuteleading to distributor, and the second circuit effecting control of theindividual distribution of fasteners to a fastening device. The firstcircuit comprises a sensing means which detects the amount of fastenerson the chute leading to the distributor, and gives a signal to actuatethe drum to feed fasteners onto the chute when there is less than acertain number of fasteners on the chute, and otherwise gives a siganlto cease actuation of the drum. The second circuit comprises a sensingmeans which detects when the fastening device requires a fastener to befed thereto, and at this time gives a signal causing the distributor totransmit a fastener to the fastening device, and otherwise gives asignal causing the distributor to remain unactuated.

A better understanding of the present invention may be had from thefollowing full description taken in conjunction with several preferredembodiments thereof with reference to the accompanying drawings, inwhich like numerals refer to like parts, and in which;

FIG. 1 is a schematic perspective view of a fastener feeding apparatuscontrollable by a drive control means according to the presentinvention;

FIG. 2 is a similar view to FIG. 1, but showing the apparatus viewedfrom a different position;

FIG. 3(a) is a side view of a rotary drum showing linkage between thedrum and an air cylinder;

FIG. 3(b) is a front elevational view of the drum of FIG. 3(a);

FIG. 3(c) is an enlarged view of a pawl portion of the linkage shown inFIG. 3(a) and 3(b);

FIG. 4 is an enlarged, perspective view of a sensing and signal meansfor detecting the presence of fasteners on a chute;

FIGS. 5(a) and 5(b) are vertical cross-sectional views of the sensingand signal means shown in FIG. 4;

FIG. 6 is a perspective and partially sectional view of a fastenerdistributor;

FIG. 7 is a perspective view of a power operated fastening device;

FIG. 8 is an exploded view of a signal means associated with thefastening device shown in FIG. 7;

FIGS. 9(a) and 9(b) and 10(a) and 10(b) are partial plan andcross-sectional views, respectively, illustrating operation of thefastening device signal means;

FIG. 11 is a circuit diagram of air flow in a drive control meansaccording to one embodiment of the invention;

FIG. 12 is a perspective view of a fastener feeding apparatus associatedwith a second embodiment of the invention;

FIG. 13 is a similar view to FIG. 12, but showing the apparatus viewedfrom a different position;

FIG. 14 is a perspective and partially sectional view of a fastenerdistributor;

FIG. 15 is a schematic cross-sectional view of the fastener distributorshown in FIG. 14;

FIG. 16 is a perspective view of a power operated fastening device;

FIG. 17 is a cross-sectional view of a signal means associated with thefastening device shown in FIG. 16; and

FIG. 18 is a circuit diagram of air flow in a drive control meansaccording to a second embodiment of the invention.

Referring initially to FIGS. 1 and 2 there is shown an example of a feedmeans, automatic control of which may be suitably effected by a drivecontrol means according to the invention. The feed means comprises agenerally basin-shaped, open-topped hopper 2, in which fasteners, suchas screws, rivets, or similar objects, may be loosely held. The hopper 2is fixedly supported in a raised position by generally vertical legs laand lb of a frame 1, which are fixedly attached to forward and rearportions of the hopper 2. The frame 1 further comprises a cross-piece10, extending from the leg 1a to the leg 1b, and is itself fixedlymounted on a baseboard 23, which may optionally, in accordance withdifferent requirements, be provided with screwholes, or other attachmentmeans, for securing thereof to a floor, or other support. A rotary drum3 is provided partially within, or constituting one side of the hopper2. The drum 3 is rotatably mounted in a generally vertical alignment,that is, the rotational axis thereof is generally horizontal, and thetop of the hopper 2 lies generally level with the center line of thedrum 3. The drum 3 is rotatably mounted on, and supported by a shaft 7asee FIG. 3(b) extending horizontally from the top of avertically-aligned support bracket 5. The lower portion of the drumsupport bracket 5 lies below the bottom of the drum 3, and is fixedlyattached to the top portion of a vertically-aligned support plate 15.The plate 15 is fixedly attached to the frame 1. Drive to the drum 3 issupplied from an air cylinder 6, acting through a cylinder rod 12, block11, linkage arms 9a, 9b, a and 10b, pawls 8, and a ratchet wheel 7. Theair cylinder 6 is actuated by a reciprocating unit 13, which is mountedon the frame 1 and is described in further detail below. The ratchetwheel 7 is mounted on the shaft 7a and is fixed'coaxially to the drum 3,whereby rotation of the ratchet wheel 7 causes rotation of the drum 3.The block 11, rod 12, and cylinder 6 are all in a generally verticalalignment below the ratchet wheel 7. The air cylinder 6 rests on thebaseboard 23, and the upper end thereof is supported by a bracket 14,which extends from, and is fixedly attached to, or integrally formedwith, the support plate 15. Control of air to the reciprocating unit 13and air cylinder 6, and to and from other parts of the drive controlmeans of the invention, is effected by a control box 22, which ismounted on the frame 1.

Referring now to FIGS. 3(a), 3(b) and 3(c) the block 11 is fixedlymounted on the upper end of the rod 12. The lower end of the rod 12connects to the piston (not shown) of the air cylinder 6 wherebyactuation of the air cylinder 6 causes the rod 12 and block 11 fixedlyattached thereto to move reciprocally upwards and downwards. The linkagearms 9a and 9b are slightly greater in length than the radius of theratchet wheel 7, and are rotatably mounted at one end on the shaft 7a.The linkage arms 10a and 10b are slightly less in length than the radiusof the drum 3, and the lower ends thereof are rotatably attached,through a pin 25, to the block 11. The upper ends of the linkage arms10a and 10b are rotatably attached, through pins 24a and 24b, to theouter ends of the linkage arms 9a and 9b respectively. Theabovementioned pawls 8a and 8b also are rotatably mounted on the pins24a and 24b, respectively, and adjacent to the periphery of, andengageable with the ratchet wheel 7. Each pawl 8a and 8b is elasticallyheld in an alignment for engaging the ratchet wheel 7 by a compressionspring 27, opposite ends of which are fixedly attached to pins 26extending from the facing sides of the pawl 8a and linkage arm 9a, orpawl 8b and linkage arm 9b. The pawls 8a and 8b are both inclined in thesame direction with respect to the ratchet wheel 7, but lie on oppositesides thereof. Therefore, during reciprocal motion of the piston of theair cylinder 6, when the rod 12 and block 11 are moved upwards, the pawl8a engages the ratchet wheel 7, thus rotating the ratchet wheel 7 anddrum 3,

whereas the pawl 8b simply rides on the outer periphery of the ratchetwheel 7. Contrariwise, when the rod 12 and block 11 are moved downwards,the ratchet wheel 7 is engaged and rotated by the pawl 8b, and is notengaged by the pawl 8a. In both cases of engagement, however, whether bythe pawl 8a or by the pawl 8b, the ratchet wheel 7, and hence drum 3, isrotated in the same direction, whereby reciprocal action of the aircylinder 6 produces unifrom rotary motion of the drum 3.

Referring back to FIG. 1, the drum 3 is rotated upwards towards the rearof the hopper 2, and downwards towards the front thereof. Around theperiphery of the inside of the drum 3, there is provided a plurality ofscoops 4, which are so shaped, and so inclined relative to the peripheryof the drum 3, as to be able to scoop up fasteners lying loosely in thehopper 2, and carry the fasteners to the highest point of rotation ofthe drum 3. At this point, as the scoops begin to move downwards,fasteners carried therein, are discharged therefrom, onto a downwardlyinclined guide tray 17. The guide tray 17 is located approximatelyvertically above the center of the hopper 2, and guides fasteners comingfrom scoops 4 into a downwardly inclined chute 16. The chute 16comprises a pair of parallel boards 16a and 16b, and extends from theguide tray 17, through the front of the hopper 2, to a distributor 18,which is located below the level of, and forward of the hopper 2. Theboards 16a and 16b are separated by a distance such that the head of afastener 38 will be supported on the upper edges thereof, as mostclearly shown in FIG. 5(a), whereby fasteners 38 will slide down thechute 16, in a correct alignment, to the distributor 18. Above the chute16, and just before the point of exit thereof from the hopper 2. thereis provided a rotatable rejector wheel 19. Fasteners 38 coming from theguide tray 17 which are not in a correct alignment, contact, and ride onthe rejector wheel 19, and are returned thereby to the hopper 2.Fasteners 38 in a correct alignment pass under the rejector wheel 19.Those portions of the boards 16a and 16b lying outside, and forward ofthe hopper 2 are supported on suitably inclined support arms 21a and21b, which extend from the support frame 1, and are integrally formedtherewith. The arms 21a and 21b also provide support, or points ofattachment, for a sensing means comprising a detection blower 20 andsignal emitters 28 and 29, as most clearly shown in FIG. 4.

Referring now to FIGS. 4, 5(a and 5(b), the detection blower 20 may beseen to comprise a board 20a, which lies above, and is generallyparallel to a lower portion of the chute l6, and in which there isformed a channel 30, through which air may pass. Air coming from an aircompressor AC is supplied into the channel 30 by a pipe 31, which isattached to, and is external to the board 20a. Air leaves the channel 30through nozzles 32a and 32b. As shown most clearly in FIG. 5, thenozzles 32a and 32b lie directly above the chute 16, and are so inclinedthat air coming therefrom is directed downwards between the boards 16aand 16b. The nozzle 32a lies above a higher point of the chute 16 thanthe nozzle 32b. Still referring to FIGS. 4, 5(0) and 5(b), the signalemitters 28 and 29 are situated directly below the nozzles 32a and 32b,respectively. The signal emitters 28 and 29 are identical inconstruction, and the description will proceed below in reference to thesignal emitter 28 only, it being understood that the description isequally applicable to the signal emitter 29.

The signal emitter 28 as in the shape of a generally yoke-shaped elementcomprising two block portions" 28a and 28b, which are attached by astrip portion 28c, and between which there is a gap 33a. In the blockportions 28a and 28b there are formed passages 34a and 35a,respectively, or air. The air passages 34a and 35a, comprise generallyhorizontal portions which communicate with the gap 33a, and portionsleading downwards to the bottoms of the block portions 28a and 28b,respectively. The horizontal portions of the air passages 34a and 35a,are aligned with one another, whereby air coming from the air passage34a is directed into the air passage 35a, as described in further detailbelow. Connection pieces 36a and 36b are fixedly inserted in and projectfrom the downwards portions of the air passages 34a and 35a,respectively. Air conduits 36a and 37a are fixedly attached to theconnection pieces 36a and 37a, respectively. The signal emitter 29similarly comprises block portions 29a, 29b, connecting strip 29c, andgap 33b, in a generally yoke-shaped element, air passages 34b and 35b,connection pieces 36b and 37b, and air conduits 36b and 37b. The airconduits 36a and 36b connect to a main supply line leading from the aircompressor AC. The air conduits 37a and 37b connect to control inputports 78A and 78B of a NOR element 78, respectively as described infurther detail below in connection with FIG. 11.

Referring more particularly to FIGS. 4, 5(a) and 5(b), air coming fromthe air compressor AC, passing through the air passage 34a or 34b,traversing the gap 33a, or 33b, and entering the corresponding airpassage 35a or 35b constitutes an interruptable jet which may beinterrupted by air directed by the nozzle 32a, or 32b, downwards betweenthe boards of the chute 16. In FIG. 5(b), presuming there are nofasteners 38 on the chute 16, the air jets of both the signal emitters28 and 29 are interrupted by air from the nozzles 32a and 32b,respectively, and therefore there is no output from either of the signalemitters 28 and 29. If the number of fasteners 38 on the chute 16 issuch that the chute 16 is filled thereby from the bottom of the chute 16to the location of the lower signal emitter 29, the presence of afastener 38 between the nozzle 32b and the chute 16 prevents air fromthe nozzle 32b from interrupting the jet across the gap 33b of thesignal emitter 29, as illustrated in FIG. 5(a). The signal emitter 29accordingly produces an output, along the conduit 37b to the NOR element78. (See FIG. 11.) Similarly, the upper signal emitter 28 produces anoutput, if fasteners 38 on the chute 16 extend to the location of thesignal emitter 28. Referring now to FIG. 6, the bottom end of the chute16 is fixedly attached to a fixed board 41a in the abovementioneddistributor 18 by connector boards 40. The distributor 18 comprises amain housing 41, a fixed block 48, which is fixedly attached to the rearboard 41a of the housing 41, and a slide block 44, which is slidablebetween the fixed block 48 and main housing 41. Within the main housing41 there is formed a cylinder 42, which is generally at right-angles tothe longitudinal axis of the chute 16. Cylinder heads 46 and 47 areprovided on the exterior of the main housing 41, at opposite ends of thecylinder 42. A spring-loaded plunger 43 is slidably mounted in thecylinder 42. A spring 42a mounted in the cylinder 42 and on theplunger43 normally urges the plunger 43 to take up a position in which one end43a thereof projects beyond the outer side of the cylinder head 46 andis external to the main housing 41. In the fixed block 48, a littleremoved from the junction of the.block 48and chute 16, there is formed afastener guidepassage 39 which extends downwards to, and communicateswith one end of a connection piece 49. The other end of the connectionpiece 49 is connected to a distributor pipe 50. The distributor pipe 50leads to a feed-in pipe portion 57 of a power-operated fastening device51 (described below). One end of the slider block 44 is fixedlyconnected, through a connection plate 45, to the outer end 43a of theplunger 43, whereby movement of the plunger 43 in the cylinder 42 causesthe slide bar 44 to move laterally with respect to the bottom end of thechute 16. In the slide bar 44 there is formed a cut-out portion 44a,which is of suitable dimensions for the accommodation of one fastener38. When the plunger end 43a is normally extended outwards with respectto the main housing 41, due to the connection through the connectionplate 45, the slide block 44 is carried to a position in which thecut-out portion 43a lies exactly opposite the bottom of the chute 16,whereby a lowermost fastener 38 in the chute 16 may leave the chute 16and enter the cut-out portion 44a.

The main housing 41 also has an inlet which communicates through anormally closed switch valve B2 to a main air supply from the aircompressor AC. The switch valve B2 is opened by input air coming fromone outlet port 81 F1 of a bistable element 81 (described below inconnection with FIG. 11.). When the switch valve B2 is thus opened flowof air from the main supply acts on the plunger 43, to cause the plunger43 to move inwards with respect to the main housing 41, and at the sametime a portion of this flow of air is supplied to the fastener guidepassage 39. When the plunger 43 is thus moved inwards, the slide block44 is carried to a position in which the cut-out portion 440 comes intoalignment with the guide passage 39, whereby a fastener 38 having leftthe chute 16 and entered the cutout portion 44a is carried to the guidepassage 39, guided therethrough to the connector piece 49, and thencethrough the distributor pipe 50 and feed-in pipe portion 57, into thefastening device 51. When the valve B2 is closed, the air supply to thedistributor 18 is cut, and the plunger 43 and slide block 44 arereturned by the force of the spring 420 to the original position inwhich the slide block cut-out portion is in line with the bottom of thechute 16, and can receive the next fastener 38, as shown in FIG. 6.

In reference now to FIG. 7, the fastening device 51 comprises a mainunit 54 and a slide shaft 55 which is slidably mounted in the main unit54, and is normally held in a forwardly extended position relativethereto by a spring 56. The abovementioned feed-in pipe portion 51 feedsfasteners 38, one at a time, into line with an outlet hole 58 at theforward end of the fastening device 51. A handle 59 is attached to thefastening device 51, to facilitate manipulation thereof. The fasteningdevice 51 is also provided with conventionally known means for actuatinga driver 83, which extends along the longitudinal axis of the fasteningdevice 51 to the vicinity of the outlet hole 58, and which screws, orotherwise attaches, fasteners 38 to external objects. The fasteningdevice 51 is actuated ina conventionally known manner, and uponactuationthereof, theslide I shaft 55 is slid into themain unit 54, against theforce of the spring 56. A signal emitter 52 having a cover plate 77 isattached by means of screws 53a and 53b to the side of the main unit 54.A dog 62 is fixedly attached to the rear end of the slide shaft 55. Thedog 62 contacts and actuates a hook element 70, which cntrols themovement of a swivel block 68, in the signal emitter 52, as shown inFIGS. 9(a) and 9(b).

Referring now to FIGS. 8, 9(0), 9(b), (a) and 10(b), the signal emitter52 comprises a portion forming a cylinder 63. An air inlet 60 and an airoutlet 61 are provided near one end 63a of the cylinder 63. The inlet 60and outlet 61 are aligned with one another, and connect respectively tothe control port 79A of a monostable element 79, and to a line P4leading to the main air supply from the air compressor AC, as shown inFIG. 1 l. A spool 64 is slidably housed in the cylinder 63. One end ofthe spool 64 is in the form of an extension 66, which extends out of thecylinder 63 beyond the other end 63b thereof. Near the other end of thespool 64, inside the cylinder 63, there is formed an air passage 67,which is radial with respect to the spool 64, and extends completelytherethrough. The spool 64 is spring-loaded by a spring 65, which exertsa constant force urging the spool 64 towards the end 63b of the cylinder63, and into a position in which the air passage 67 is remote from theair inlet 60 and outlet 61, whereby air does not pass from the inlet 60to the outlet 61, as shown in FIG. 9 (b).

The spool extension 66 is contactable by the abovementioned swivel block68. The swivel block 68 is generally rectangular, and is rotatablymounted on a pin 69, which passes through a generally central point ofthe block 68. One end of a compression spring 72 is fixedly attached toa pin 73a, which is fixedly attached to a point on one half 68a of theblock 68. The other end of the spring 72 is fixedly attached to a pin73b, which is fixedly attached to a solid portion 74 of the signalemitter 51. The spring 72 exerts a constant force urging the swivelblock 68 to turn about the pin 69 in such a manner that the other half68b thereof presses against the spool extension 66, as shown in FIG. 10(a). In this configuration, the spool 64 is forced to move inwards withrespect to the cylinder 63, against the force of the spring 65, and intoa position in which the air passage 67 formed therein comes intoalignment with the air inlet 60 and outlet 61, whereby air can pass fromthe inlet 60 to the outlet 61, as shown in FIG. 10 (b).

The alignment of the swivel block 68 is not, however dependent uniquelyon the force exerted by,the spring 72, but is also determined by theposition of the abovementioned hook element 70. The hook element 70 isslidably supported on a plate 76, and comprises hook ends 70a and 70b, amain portion 700, and a block portion 70d. The main portion 70c isgenerally parallel to the longitudinal axis of the fastening device 51.The block portion 70d is fixedly attached, or integrally formed with themain portion 700, and extends towards and contacts the outer edge of thehalf 68a of the swivel block 68. The hook ends 70a and 70b extendatapproximately right-angles from the main portion 700 and towards thefastening device 51, the hook end 70a being nearer the front end of thefastening device 51, and the hook end 70b being nearer the rear endthereof (FIGS. 9 (b), 10 (b)). When the slide shaft 55 of the fasteningdevice 51 is in a normal forwardly extended position relative to themain unit 54, that is, during non-use of the fastening device 51, thedog 62 attached to the rear end of the slide shaft 55 contacts andpushes the hook end 700, whereby the hook element is movedslightly'forwards, the block portion 700' contacting the swivel block 68aids the spring 72, and the block 68 is turned in such a manner that thehalf 68b thereof pushes the spool extension 66, and causes the spool 64to move rearwards into a position in which the air passage 67 is in linewith the air inlet 60 and outlet 61, as shown in FIGS. 10(a) and 10(b).In other words, during non-use of the fastening device 51, there iscommunication between the signal emitter air inlet 60 and outlet 61.

When the fastening device 51 is in operation, the slide shaft 55 movesinwards with respect to the main unit, and in this case, the dog 62contacts and pushes the hook end 70b, whereby the hook element 70 ismoved slightly rearwards. The hook element block portion 70d thereforecauses the swivel block 68 to swivel against the force of the spring 72,whereby the block half 68b is moved out of contact with the spoolextension 66 (FIG. 9 (a)), and the spool 66 is moved by the force of thespring 65 towards the forward end 63a of the cylinder 63, and into aposition in which the air passage 67 in the spool 66 is remote from theair inlet 60 and outlet 61 (FIG. 9 (b)). In other words, when thefastening device 51 is in use to attach a fastener 38 to an externalobject, air cannot pass from the inlet 60 to the outlet 61. During useof the fastening device 51, air pressure at the inlet 60 builds up, andsubsequently acts to trigger the monostable element 79 (described below)when use of the fastening device 51 terminates, and communication isagain established between the inlet 60 and outlet 61.

Reference is now had to FIG. 11, in which there is shown a circuitdiagram of fluid paths in a drive control means according to a firstembodiment of the invention. In the drawing, the chain-dot line portionindicated generally by 22 corresponds to the control box 22 mounted onthe frame 1, and other previously described elements are schematicallyrepresented by corresponding numbers.

Air for the entire circuit is initially supplied from the air compressorAC, or any other suitable means, at a pressure of 4 5 kg/cm. The airsupplied first passes through a filter F1, and then divides into twopaths leading respectively to a first control circuit, which controlssupply of fasteners 38 from the hopper 2 to the distributor 18, and asecond control circuit which controls distribution of fasteners 38 fromthe distributor 18 to the fastening device 51.

After passing through the filter Fl, air divides and passes through aregulator R1 or through an oiler 01. Air which has passed through theoiler 01 contains oil for the lubrication of various mechanical parts,and is supplied along a line P3 connecting to the fastening device 51,and along a line P6 connecting to a switch valve Bl, which isspring-loaded in a normally closed position, and which connects to anoscillator 82 contained in the abovementioned reciprocating unit 13(FIG. 2). The valve B1 is opened by output supplied along a line P8,from an output port 80F 2 of a bistable element 80.

The oscillator 82 has two compartments, an upper compartment 82a and alower compartment 82b, and is movable to two positions, an upperposition U and a lower position L. Presuming the valve B1 'is open,whenthe oscillator 82 is in the lower position L the upper compartment82a thereof provides a connection between the line P6 and a lower pipe612' connecting to the air cylinder 6. When air is supplied through thelower inlet pipe 6b the piston of the air cylinder 6 is raised, and atthe same time, a portion of this inlet air is led through a feedbackline 6b to apply pressure to raise the oscillator 82 to the upperposition U. Air is exhausted from the cylinder 6 through an upper pipe6a connecting thereto. When the piston reaches a topmost position thepressure of air through the feedback line 6b becomes sufficient to raisethe oscillator 82 to the upper position U. When the oscillator 82 is inthe upper position U, the lower compartment 82b thereof provides aconnection between the line P6 and the upper pipe 6a. Air suppliedthrough the upper inlet pipe 6a causes the piston of the air cylinder 6to move downwards, air being exhausted from the cylinder 6 through thelower pipe 612, and at the same time a portion of this inlet air is ledthrough a feedback line 6a to apply pressure to move the oscillator 82to the lower position L. When the piston of the air cylinder 6 reaches alowest position, the pressure of air supplied through the feedback line6a becomes sufficient to move the oscillator 82 to the lower position L,whereupon the above described process is repeated. The piston of the aircylinder 6 is therefore moved reciprocally, and the drum 3 is rotated,and transfers fasteners 38 from the hopper 2 onto the chute 16, asdescribed earlier.

Air which has passed through the relay R1 is supplied to a main line P1,and to a line P2. The regulator R1 is spring-loaded to normally permitpassage of air therethrough to the lines P1 and P2. A portion of the airpassing through the regulator R1 is supplied to a feedback line R1, andacts to oppose the force of the spring holding the regulator R1 open,whereby at certain pressures of air passing through R1, the force of theair supplied along the feedback line R1 is sufficient to move theregulator R1 to a closed position, and the regulator R1 is not returnedto an open position until the pressure of the air supplied along thefeedback line R1 drops to a certain value.

Air supplied along the main line P1 passes through a switch S1, and arestriction orifice to the channel 30 of the detection blower 20. A lineP11 leading from the line P1, and containing a restrictionorifice,supplies air to the signal emitters 28 and 29. The line P2 leads to anormally closed switch valve B2, which connects to the distributor 18.The distributor 18 is also connected by a feedback line to the line P2,in order to establish. requisite air pressures to feed the fastener 38in the distributor 18.

Output from the emitter 28, which is higher on the chute 16, is suppliedthrough a line P to two lines P101 and P102. The line P101 leads to acontrol port 78A of the NOR element 78. The line P102 connects to aninput of a delay valve DV1. The output of the delay valve DV1 connectsto a control port 80B of the above-mentioned bistable element 80. Thedelay valve DV1 is also connected through a line P103, containing arestriction orifice, to the main supply line P1.

Output from the lower signal e'initter 29 is supplied along a line P9 tothe other control port 78B of the NOR element 78. The NOR element 78 hasan output port 78F, at which output is produced'only when input to boththe control ports 78A and 78B'is zero or none. The NOR element outputport 78F connects to the other control port 80A of the'bistable element80.

Input to the bistable element from the NOR element 78 causes output fromthe bistable element 80 to be produced at the output port 80F2. Inputfrom the delay valve DV1 causes the bistable element 80 output to beproduced at the other outlet port 80F1. Upstream supply to the elements78 and 80 is supplied along lines all and a12, which lead from a line a1connecting to a line a. The line a connects through a restrictionorifice to the main line P1.

A line P4 containing a restriction orifice provides a connection betweenthe main line P1 and the air inlet 60 of the fastening device signalemitter 52. The outlet 61 of the emitter 52 is connected to theabovementioned monostable element 79, which functions as a one-shotmultivibrator, by a line P5. Output from the monostable element 79 issupplied as input to a control port 81B of a bistable element 81. Thisinput causes the bistable element to produce output at an output port81F1, which connects to a line P7 leading to the normally closed switchvalve B2. When output is supplied from the bistable element output port81Fl, along the line P7, the switch valve B2 is moved against the forceof a spring holding it closed, to a position in which the valve B2provides communication between the distributor 18 and the supply lineP2, whereby the distributor 18 is actuated to supply a fastener 38 tothe fastening device 51, as described above. Input to the other controlport 81A of the bistable element 81 is supplied from a timer TM.

The timer TM also connects to the line P7, both directly and through agage valve TMl. The timer TM is further connected to the main line P1through a line Tl containing a restriction orifice. Input from the timerTM to the bistable element 81 causes output from the element 81 to beproduced at the other output port 81F2 thereof, whereby air supply alongthe line P7 to the switch valve B2 is cut, the valve B2 is returned by aspring force to a closed position, air supply along the line P2 to thedistributor 18 is cut, and operation of the distributor 18 ceases.Upstream supply to both the elements 79 and 81 is supplied along linesa2l and 022, which lead from a line a2 connecting to the abovementionedline a.

The description will now proceed in reference to the operation of thefirst control circuit which maintains a supply of fasteners 38 to thedistributor 18.

To start operation the switch S1 is switched to permit air coming fromthe air compressor AC, and through the filter F1 and regulator R1, toflow into the main line P1, whereby air is supplied to the detectionblower 20 and the upper and lower signal emitters 28 and 29. Presumingnow there are no fasteners on the chute 16, the air jets across both thegaps 33a and 33b of the signal emitters 28 and 29 are interrupted by airprojected downwards from the nozzles 32a and 32b, respectively (see alsoFIGS. 5(a), 5(1)) and 6). There is therefore no output from the emitter28 along the line P10, or from the emitter 29 along the line P9, andaccordingly no input along the line P102 to the delay valve DV1, oralong the lines P101 and P9 to the control ports 78A and 78B of the NORelement 78. There being no input at either control port 78A and 78B, anoutput from the NOR element output port 78F is supplied as input to thecontrol port 80A of the bistable element 80, thereby switching outputfrom the element 80 to the output port 80F2. This output is suppliedalong the line P8 to open the switch valve Bl, whereby air coming fromthe oiler 01 and along the line P6 is supplied to the oscillator 82, theair cylinder 6 is actuated, and fasteners 38 are supplied onto the chute16 by the drum 3. The supply of fasteners 38 onto the chute 16 isgenerally faster than the use thereof by the fastening device 51, andthe supply of fasteners 38. ready for distribution, on the chute 16steadily builds up. When the number of fasteners 38 on the chute 16 issuch that a fastener 38 is held between the detection blower nozzle 32band the lower signal emitter 29, the signal emitter 29 produces anoutput along the line P9 to the control port 78B of the NOR element 78,while output of the upper signal emitter 28 continues to be zero.Conditions along the lines P10, P101 and P102 therefore continueunchanged, but output at the NOR element output port 78F, ceases, andthere is no input to the control port 80A of the bistable element 80.However, there is no switching input to the control port 80B either, andso output of the bistable element 80 continues to be produced at theoutput port 80F2, and the drum 3 continues to be actuated to supplyfasteners 38, from the hopper 2, onto the chute 16. When the fasteners38 on the chute 16 reach the level of the upper signal emitter 28, airfrom the nozzle 32a can no longer interrupt the jet across the gap 330of the emitter 28, and so the emitter 28 produces an output which istransmitted along the lines P10, P101 and P102. The input along the lineP101 to the NOR element control port 78A does not change the state ofthe NOR element 78, since there is already an input at the port 78B. Theoutput signal transmitted along the line P102 is supplied to the delayvalve DVl. After about 0.5 seconds the delay valve DVl produces anoutput which is supplied as input to the control port 80B of thebistable element 80, and switches the output of the element 80 to theport 80 Fl thereof. Air supply along the line P8 is therefore cut, andthe switch valve B1 is returned by spring force to a closed position,thus cutting supply to the oscillator 82 from the line P6, wherebyaction of the air cylinder 6 and rotation of the drum 3 cease, andfasteners 38 are no longer supplied to the chute 16. As fasteners 38 aredistributed by the distributors 18 to the fastening device 51, for usethereby, the number of fasteners 38 on the chute 16 decreases. When thehighest fastener on the chute 16 moves to below the level of the lowersignal emitter 29, the abovedescribed process is repeated.

In reference now to the second control circuit, which effects transferof fasteners 38 from the distributor 18 to the fastening device 51 (FIG.8), presuming that there is no fastener 38 in the fastening device 51,the second control circuit is actuated by causing the slide shaft 55 ofthe fastening device 51 to slide into the main unit 54 thereof, that is,by actuating the fastening device 51 as though there were a fastener 38therein. This cuts communication between the air inlet 60 connectedthrough the line P4 to the main line P1, and outlet 61 connecting to theline P FIGS. 9(a) and 9(b). Air pressure builds up at the inlet 60, andwhen the slide shaft 55 is allowed to move out of the main unit 54, andcommunication is established between the inlet 60 and outout 61 FIGS.10(a) and (10b), a trigger signal is supplied along the line P5 to theinput port 79A of the monostable element 79. The monostable element 79thereupon produces an output, which is supplied as input to the controlport 81B of the bistable element 81, and causes output of the bistableelement 81 to appear at the output port 81F1 thereof. Output from themonostable element 79 ceases rapidly, because the flow of air theretobecomes steady, and because of the impedance of the line P5, but thebistable element 81 remains switched to produce output at the port 81F1,until receipt of an input at the control port 81A, as described below.

Output from the bistable element 81 is supplied along the line P7 toopen the switch valve B2, and also to the timer TM. When the valve B1 isopened air is supplied to the distributor 18 through the line P2, and afastener 38 is supplied to the fastening device 51, as described above.While the distributor 18 is thus in operation, air is being supplied tothe timer TM, and after a set time, the timer TM supplies a switchinginput, along the line T2, to the control port 81A of the bistableelement 81. Output from the bistable element 81 is therefore switched tothe output port 81F2, supply along the line P7 is cut, and the switchvalve B1 is returned by spring force to a closed position, wherebysupply along the line P2 to the distributor 18, and operation of thedistributor 18 ceases. In other words, the duration of the functioningof the distributor 18 is determined by the setting of the timer TM. Whenthe fastening device 51 is actuated to attach the fastener 38 suppliedthereto to some object, the abovedescribed process is repeated.

The description of the invention now proceeds in reference to a secondembodiment thereof, which is shown in FIGS. 12 through 18.

Referring now to FIGS. 12, 13 there is shown a fastener feed assemblywhich functions in a generally similar manner to that of the feedassembly shown in FIGS. 1, 2, and may be suitably controlled by a drivecontrol means according to the second embodiment. The fastener feedassembly shown in FIGS. 12 and 13 comprises a hopper 85 supported on aframe 84, and a drum 86 which is provided with scoops 87 and, whenrotated, transfers fasteners 38 from the hopper 85 to a guide tray 102which guides fasteners 38 into a chute 101. The chute 101 comprises twoparallel boards 101a, 101b, which are downwardly inclined and extendfrom a point generally above the hopper 85 to a distributor 103, whichis located below the level of, and forward of the hopper 85. Theportions of the boards 101a and 10lb which are outside the hopper 85 aresupported on support arms 106. The forward portion of chute 101 is alsoprovided with boards 105, which are for the purpose of maintainingsuitable separation between fasteners 38 sliding down the chute 101.Just before the exit of the chute 101 from the hopper 85 there isprovided a rejector wheel 104, which returns incorrectly alignedfasteners 38 to the hopper 85. The drum 86 is rotatably mounted on ashaft 89, which is supported by a frame 88. The frame 88 is supported bya vertical plate 100, which is fixedly attached to the frame 84. Abracket 99 extending generally at rightangles from the plate 100provides support for a vertically aligned cylinder rod 96, the lower endof which is fixedly attached to the upper end of the piston of avertically aligned air cylinder 90, whereby actuation of the aircylinder 90 causes the cylinder rod 90 to move reciprocally upwards anddownwards. The drum 86 is driven by rotation of a ratchet wheel 91,which is fixed thereto, and mounted coaxially therewith on the shaft 89.The ratchet wheel 91 is rotated by pawls 92a, 92b provided respectivelyat ends of linkage arms 93a, 93b, the other ends of which are rotatablymounted on the shaft 89. Ends of linkage arms 94a, 94b are in rotatableattachment to the linkage arms 93a, 93b, respectively. The other ends ofthe linkage arms 94a, 94b are in rotatable attachment to a block 95,which is fixedly mounted on the upper end of the cylinder rod 96,whereby actuation of the air cylinder 90 causes rotation of the drum 86,in the same manner as described in reference to the feed apparatus ofthe first embodiment.

In the second embodiment, there is not provided an oscillator unit 13,but control of the air cylinder 90 is effected through a reciprocatorvalve 98 and a switching element 97. The reciprocator valve 98 issupported at a point on the plate 100 near to the cylinder rod 96, andcomprises a flap 98a, which extends towards the cylinder rod 96. Theswitching element 97 is fixedly mounted on, and moves reciprocallyupwards and downwards together with the cylinder rod 96, and comprise anupper switching extension 97a and a lower switching extension 97b. Thevalve flap 98a is pushed by the lower extension 97b or pulled by theupper extension 97a, according to whether the cylinder rod 96 reaches atopmost or lowermost position, whereby the recipricator valve 98 isactuated to control air flow to the air cylinder 90, as described infurther detail below. Also, in the second embodiment the control box 22is replaced by a control section CS located below the hopper 85, andcomprising throttle valves 150 and 155, switch valves 149 and 153,changeover valves 146 and 151, and starting button 156a, which aredescribed in further detail below.

Referring to FIGS. 14 and 15 the lower end of the chute 101 is connectedto the distributor 103 by connector boards 108. The distributor 103functions in the same manner as the fastener distributor described inreference to the first embodiment, and comprises a main housing 109, afixed block 116, which is fixedly attached to the main housing 109 andin which there is formed a fastener guide passage 107 communicating witha connection piece 117, and a slide block 112 which is slideable betweenthe fixed block 116 and main housing 109 and comprises a cut-out portion112a, wherein fasteners 38 may be carried from the bottom of the chute101 to the guide passage 107. A spring-loaded plunger 111 is slidablymounted in a cylinder 110, which is formed in the main housing 109, andat opposite ends of which there are provided cylinder heads 114, 115.One end of the plunger 111 is exterior to the main housing 109, and isconnected to one end of the slide block 1 12 by a fixedly attachedconnection plate 113, whereby actuation of the plunger 111 also actuatesthe slide block 112. Air supplied to it in a manner described belowactuates the distributor 103 to transfer a fastener 38 from the chute101 to the guide passage 107. Fasteners 38 thus transferred are moved byair pressure to the connection piece 117, through a distribution pipe118 connected thereto, and to the feed-in pipe 123 of a fastening device119.

In FIG. 16, the fastening device 119 may be seen to comprise a forwardportion 124, a pneumatically driven screwdriver 125, or similar means, aslide shaft 124a, a main unit 120, and a handle 126. The slide shaft124a slides into the main unit 120 when the fastening device 119 is inuse and is heldforwardly extended, relative to the main unit 120, by aspring 127, during non-use of the fastening device 1 19. A dog 128 isattached to a rear portion of the slide shaft 124a.

When the fastening device 119 is being used to attach a fastener-38 tosome object, and the slide shaft 124a is slid into the main unit 120,the dog 128 actuates a signal emitter 121, which is fixedly attached tothe main unit 120 by screws 122a 122b.

Referring now to FIG. 17, the signal emitter 121 may be seen to comprisea main block in which there are formed valve chambers 139a and 139b,connecting channel 136a, and outlet channel 136b. The longitudinal axesof the valve chambers 139a and 139k are generally parallel to thefront-to-rear, longitudinal axis of the signal emitter 121, and thechambers 139a and 13% are formed in line with one another, chamber 139abeing forward of chamber 13%, with respect to the signal emitter 121.

The rear end of the valve chamber 13% opens at the rear surface of themain block 130 and forms an inlet 131, into which a connector 134 issecurely inserted. An inlet tube 133 is fitted on the connector 134. Thetube 133 brings air supplied along a line Lla (described below) to thesignal emitter 122. The forward end of the chamber 13% is narrowed andcommunicates with a small diameter passage 135, which also communicateswith the rear end of the other valve chamber 139a. The passage isnormally sealed by a ball 143 which is normally urged to the forward endof the chamber 13% by an expansion spring 142 provided within thechamber 139]).

Still referring to FIG. 17, the forward valve chamber 139a extends fromthe passage 135 to the front of the main block 130. A slide rod 129 isslidably mounted in the chamber 139a. The forward portion of the sliderod 129 constitutes a large diameter portion fitting slidably into, andthrough, a stop screw 141 which is mounted in the front end of thechamber 139a. The rear portion 12% of the slide rod 129 forms a narrowdiameter portion which may pass through the passage 135 and extend intothe rear valve chamber 13%. An expansion spring provided in the chamber139a and mounted around the slide rod 129 exerts a constant force urgingthe slide rod 129 towards the front end of the chamber 139a, and into aposition in which the forward end 129a of the slide rod 129 projectsforwards, beyond the front surface of the main block 130. When the sliderod 129 is in this configuration, the rear portion 12917 thereof doesnot extend into the passage 135. When the fastening device 119 isactuated and the slide shaft 124a thereof is slid into the main unit120, the dog 128 attached to the slide shaft 124a contacts the forwardend 129a of the signal emitter slide rod 129, and pushes the slide rod129 rearwards into the chamber 139a, against the force of the spring140. When the slide rod 129 is thus moved rearwards, the rear portion12% thereof passes into and through the passage 135, and pushes the ball143 rearwards, whereby air entering the inlet 131 may pass through thechamber 139b, through the passage 135, and into the chamber 139a.

The abovementioned connecting channel 136a communicates with and isformed generally at right-angles to the chamber 139a. The outlet channell36b is a continuation of the connecting channel 136a, formed generallyat right-angles thereto, extending generally parallel to the rear valvechamber 139b, and forming an outlet 132 at the rear surface of the mainblock 130. A connector 137 is securely inserted in the outlet 132, andis connectedto a tube 138, which supplies air to a line L4 (describedbelow). When the slide rod 129 is pressed rearwards by the dog 128, airentering through the inlet 131 may therefore pass through the chamber13% and passage 135, into the chamber 139a, and from the chamber 139into and through the channels 136a and 136b to the outlet 132. In otherwords unlike the distribution signal emitter of the first embodiment,the signal emitter 121 of the second embodiment produces a signal outputwhen the fastening device 119 is in use.

Reference is now had to FIG. 18, which is a schematic circuit diagram offluid paths in the drive control means according to the secondembodiment of the invention.

Air is supplied to the circuit from an air compressor AC, or othersuitable means. Air coming from the air compressor AC first passesthrough a filter 144, and then divides into two paths constituted bylines L1 and L2. Air following the line Ll passes through an oiler 145,which provides oil for lubrication of various mechanical parts. The lineL1 leads to two lines Lla and Llb which connect respectively to thefastening device 1 19 and the inlet tube 133 of the fastening devicesignal emitter 121, as indicated in the upper left-hand portion of FIG.18.

Branch lines L11, L12 and L13 lead off from the line Ll (lowerright-hand portion of FIG. 18). The line L11 is connected to a switchvalve 153 which is springloaded in a normally closed position. When thevalve 153 is opened, in a manner described below, the valve 153 connectsthe line L11 to a line L14. The line L14 leads through a valve 156 to aline L15. The valve 156 has two positions which are position I, in whichthe valve connects the line L14 to the line L15, and position II, inwhich the valve 156 connects the branch line L12 to the line L15. Thevalve 156 is spring-loaded to be normally in position I, and may bemoved to position II by depression of the abovementioned start button156a provided on the control section CS below the hopper 85. The lineL15 leads to the above-mentioned reciprocator valve 98 which is providedon the support bracket 100 and is actuated by the switch element 97mounted on the cylinder rod 96 (FIG. 12). Action of the valve 98 will bedescribed further below.

Still referring to FIG. 18, the line L13 supplies air to an oscillator154 which drives the air cylinder 90. The oscillator 154 has twopositions, which are position U and position L. When in position U, theoscillator 154 connects the line L13 and a lower pipe 90b leading to theair cylinder 90. In this case, air is supplied into the air cylinder 90,causes the piston thereof to rise, and exits through an upper pipe 90a.When in position L, the oscillator 154 connects the input line L13 tothe upper pipe 90a of the cylinder 90, whereby air entering the cylinder90 causes the piston thereof to move downwards, and exits through thelower pipe 90b. The oscillator 154 is spring-loaded to be normally inthe position U, and may be moved to position L by the pressure of airsupplied along a line L16 which connects to the reciprocator valve 98.

The reciprocator valve 98 has two positions, in which it is open orclosed, respectively. When the piston of the air cylinder 90 reaches alowermost position the switch extension 97a of the switch element 97pulls the valve flap 98a, and closes the valve 98. In this situation,air coming along the line L15 cannot pass through the valve 98, andtherefore no air issupplied along the line L16; the oscillator 154 is inthe position U, and air supplied along the input line L13 enters thelower pipe b and causes the piston of the air cylinder 90 to rise. Whenthe piston reaches a topmost position, the switch extension 97b pushesthe valve flap 98a and opens the valve 98. The valve 98 now connects thelines L15 and L16, and the pressure of air supplied along the line L16pushes the oscillator into position L, and the piston of the aircylinder 90 is moved downards. The above described action is repeatedfor as long as air is supplied along the line L15. As noted earlier, airis su'pplied along the line L15 only when the valve 153 is open toconnect the lines L11 and L14, or when the starter button is depressedto connect the lines L12 and L15.

Air entering the line L2 first passes through a regulator 147, which,similarly to the regulator R1 of the first embodiment, is provided witha feedback line to ensure that pressure along the line L2 does notexceed a certain value. The line L2 supplies air to lines L21, L22 andL23, which are respectively connected to a changeover valve 151, aswitch valve 149, and a changeover valve 146.

The changeover valve 146 is connected to a line L24 leading to an airtank 148, and has two positions, 146A and 146B. The valve 146 isspring-loaded to be normally in position 146A, and in this positionprovides communication between the line L24 and a line L41, which leadsto the switch valve 149, and which also is connected to a line L42leading to a vent 150. Flow of air through the vent is controlled by athrottle valve 150a. The valve 146 may be moved against thespring-loading force, to position 146B by pressure of air supplied alongthe abovementioned line L4, which connected to the outlet tube 138 ofthe fastening device signal emitter 121. The line L4 also supplies airto a line L5, which leads to the changeover valve 151. When the valve146 is in position 146B, it connects the lines L23 and L24, anddisconnects the lines L24 and L41.

The switch valve 149 is spring-loaded to be normally closed, but may bepushed into an open position by pressure of air supplied along the lineL41. When open, the valve 149 provides connection between the line L22and a line L25. The line L25 leads to and supplies air to actuate thedistributor 103 to supply a fastener 38 to the fastening device 119.

The changeover valve 151 connected to a line L26 leading to an air tank152, and has two positions, 151A and 151B. The valve 151 isspring-loaded to be nor mally in position 151A, and in this position thevalve 151 connects the line L26 to a line L51, which leads to theabovementioned switch valve 153, and which is also connected to a lineL52 leading to a vent 155. Flow of air through the vent is controlled bya throttle valve 155a. Air supplied along the line L51 pushes the switchvalve 153 open, in which case the valve 153 connects the lines L11 andL14, as described above. The changeover valve 151 may be pushed toposition 151B by pressure applied thereto by air flowing along the lineL5. In position 151B, the valve 151 connects the lines L21 and L26, anddisconnects the lines L26 and L51.

The description will now proceed first in reference to the action of theabove described circuit in causing fasteners 38 to be supplied from thedistributor 103 to the fastening device 119, and then in reference tothe action of the circuit in causing the drum 86 to supply fasteners 38from the hopper 85 to the chute 101. These

1. In a fastener feed apparatus including a hopper section for bulkstorage of fasteners, a transfer means operatively positioned fortransferring fasteners from said hopper section, a transfer chuteleading from said hopper section and to which fasteners are transferredby said transfer means, a distribution means connected to said transferchute for individual distribution of fasteners, and a fastening devicecoupled to said distribution means and to which fasteners are suppliedone at a time by said distribution means, the improvements whichcomprise: a drive control means comprised of a first pneumatic controlcircuit operatively coupled for drive control of said transfer means andincluding at least one delay valve and fluidic element, first sensormeans operatively positioned for detecting the state of supply offasteners on said transfer chute and emitting different control signalsin response to detection of different supply states, and a secondpneumatic control circuit operatively associated with said fasteningdevice and said distributing means for activating said distributionmeans to supply fasteners to said fastening device.
 2. A fastener feedapparatus drive control means as recited in claim 1, wherein said firstcontrol circuit includes a second sensor means comprised of a firstsignal emitter and a second signal emitter, a monostable fluidicelement, a bistable fluidic element, and a delay valve, said firstsignal emitter coupled to and supplying input to said monostableelement, said second signal emitter coupled to and supplying input tosaid monostable element and to said delay valve, said monostable elementand said delay valve coupled to and supplying inputs to said bistableelement, and said bistable element supplying output to actuate saidtransfer means in accordance with inputs received thereby.
 3. A fastenerfeed apparatus drive control means as recited in claim 1, wherein saidsecond control circuit includes a signal source coupled to and operableby said fastening device, a monostable fluidic element coupled to andreceiving input signals from said signal source, a bistable fluidicelement coupled to and receiving input from said monostable element andsupplying output to actuate said distribution means, and a timeroperatively coupled for controlling the duration of output by saidbistable element.
 4. A fastener feed apparatus drive control means asrecited in claim 1, wherein said first sensor means comprises a thirdsignal emitter and a fourth signal emitter provided at differentlocations on one side of said transfer chute and each comprising an airjet means, and a blower means provided on another side of said transferchute and comprising a first nozzle and a second nozzle, said nozzlesrespectively directing air jets to interrupt air jets generated by saidsignal emitter air jet means.
 5. In a fastener feed apparatus comprisinga hopper section for bulk storage of fasteners, a transfer meansoperatively positioned for transferring fasteners from said hoppersection, a transfer chute leading from said hopper section and to whichfasteners are transferred by said transfer means, a distribution meansfor individual distribution of fasteners connected to said transferchute, and a fastening device to which fasteners are supplied one at atime by said distribution means, the improvements which comprise a drivecontrol means comprised of a signal emission means provided on andactuated upon actuation of said fastening device, a first pneumaticcontrol circuit for actuation of said transfer means, and a secondpneumatic control circuit for actuation of said distribution means, bothsaid first and second control circuits operatively coupled for receivingcontrol inputs from said signal emission means, and including adjustablevalves controlling the duration of functioning times thereof.
 6. In aparts supply apparatus comprising a bulk reserve means, a distributorfor distribution of parts to a required location, a guide meansconnecting said bulk reserve means and said distributor, and a transfermeans operatively positioned for transfer of parts from said bulkreserve means to said guide means, the improvements which comprise afluidic drive control means including a first sensor means adjacent tosaid guide means for detecting the state of supply of parts on saidguide means and emitting different signals in response to different saidsupply states, a first control circuit operatively coupled and includinga delay valve and fluidic elements receiving input signals from saidfirst sensor means and actuating said transfer means in accordance withsaid input signals, a second sensor means operatively positioned fordetecting the state of supply of parts at said position, and emittingdifferent signals in response to different said supply states, and asecond control circuit coupled to said second sensor means and whichincludes a timer and fluidic elements receiving input signals from saidsecond sensor means and actuating said distributor to supply parts tosaid required location in accordance with said input signals.